Construction of Fe 3 O 4 -Loaded Mesoporous Carbon Systems for Controlled Drug Delivery.

Magnetite (Fe 3 O 4 ) nanoparticles as drug carriers can achieve precise drug target due to their magnetic property. However, they are easy to aggregate in the physiological environment, which obviously limits their application in drug delivery. The development of the Fe-MIL-88B-derived method to construct the Fe 3 O 4 -loaded mesoporous carbon (Fe 3 O 4 /carbon) system is a feasible strategy to solve the issue. First, iron atoms evenly distribute in the organic links through coordination bonds in Fe-MIL-88B. After the carbonization of Fe-MIL-88B, mesoporous carbon acts as a barrier to prevent the aggregation of Fe 3 O 4 nanoparticles. Herein, Fe-MIL-88B particles were fabricated by the hydrothermal method and then pyrolyzed to construct Fe 3 O 4 /carbon systems. Results showed that Fe 3 O 4 nanoparticles uniformly in situ grew on mesoporous carbon generated by the carbonization of organic components. More encouragingly, the Fe 3 O 4 /carbon system loaded with DOX demonstrated pH-responsive DOX release, efficient delivery of DOX into cancer cells, and significant cancer cell killing ability. Therefore, the Fe 3 O 4 /carbon systems prepared by the Fe-MIL-88B-derived method might open up a way for targeted and controlled drug delivery.